Butanone oxime is often used industrially as an anti-skinning agent or an oxygen scavenger in paints, and can be further used for producing methyltributanoneoximido silane or vinyltributanoneoximido silane which is used as a neutral cross-linking agent or a silicon rubber-based sealing agent. These chemical raw materials have a wide variety of applications in architectures, automobiles and pharmaceuticals.
Generally, a hydroxyl ammonium method is mainly used for producing butanone oxime. This method involves reacting butanone and acidic hydroxyl ammonium to produce butanone oxime. However, this method not only has complex steps and high equipment cost, but also produces a large amount of low-valued ammonium salts as byproducts which are detrimental to the environment. Therefore, in order to avoid harming the environment, a crystalline titanium-silicon molecular sieve (also referred to as “TS-1” molecular sieve) with an MFI structure is obtained by introducing a titanium atom into a silica network structure. The TS-1 molecular sieve is used to catalyze oxidation, such as hydroxylation of aromatic hydrocarbons, ammoxidation of alkenes, partial oxidation of alkanes, and ammoxidation of ketones, to bring about significant catalytic activities and selectivity of products.
As to ammoxidations of ketones, cyclic ketones or linear ketones can usually be selected as raw materials for reactions, U.S. Pat. No. 4,410,501, U.S. Pat. No. 4,968,842, U.S. Pat. No. 5,227,525, U.S. Pat. No. 5,312,987 and U.S. Pat. No. 6,828,459 disclose ammoxidation performed by using cyclic ketones. However, there are very few literatures related to ammoxidation of linear ketones. Chinese Patent No. 1706818 and Chinese Patent No. 101318912 disclose the uses of a TS-1 molecular sieve to catalyze oxidation to prepare linear ketoximes. Nevertheless, yields of ketoximes in these patents are poor.
Moreover, Chinese Patent No. 101544582 also discloses a method for preparing butanone oxime, which involves adding a noble metal to modify a TS-1 catalyst for the use in ammoxidation of butanone. The selectivity of butanone oxime significantly increases to 90%. However, the conversion rate of butanone is at most 10%.
Accordingly, there is a need to develop a process for preparing a ketoxime with high product selectivity, high conversion rates of the raw materials, and high yield of ketoximes.